Device for the manufacture of a row of linking components for a slide fastener

ABSTRACT

In a known process and apparatus for the production of a continuous row of linking components for a slide fastener, using a plastics thread, the plastics thread is shaped into a spiral over and between a series of studs by means of a thread guide. One of the ends of each whorl of the spiral is crushed by means of a punch to form a linking component, whilst holding the corresponding whorl between the studs. The invention provides the improvement in that, on the crushing-point side of each whorl, the corresponding portion of the thread is stretched out rectilinearly beyond the crushing point and facing the corresponding side face of the thread guide. The required point of the thread is then crushed against the thread guide, which is used as an anvil, the punch used being independent of the other working tools, and the folding back of the corresponding portion of the thread being performed only after the crushing has been carried out.

0 United States Patent [191 u 11 ,164 J o 1 Jan. 22, 1974 [54] DEVICE FOR THE MANUFACTURE OF A 3,353,217 11/1967 Bashover 425/391 ROW or LINKING COMPONENTS FOR A g pe 2/2:

, opovltsc SLIDE FASTENER 3,672,805 6/1972 Porepp 425/814 [75] Inventor: Horst Jakob, Choisy-le-Roi, France [73] Assignee: Societe Financiere Francaise De Licenses Et Brevets, Chosy-le-Roi, France [22] Filed: Oct. 5, 1971 [21] Appl. No.: 186,612

[30] Foreign Application Priority Data Oct. 8, 1970 France 7036379 [52] US. Cl. 425/397, 425/814 [51] Int. Cl. 1329c 17/00 [58] Field of Search425/8l4, 391, 397', 29/207.5 R,

[5 6] References Cited UNITED STATES PATENTS 3,229,362 1/1966 Yoshida 264/281 X 3,541,638 11/1970 Porepp 29/2075 R X 3,176,637 4/1965 MacFee 425/814 3,197,537 7/1965 Hansen 425/814 3,220,055 11/1965 Steingruebner 425/814 X 3,262,157 7/1966 Fujisaki 425/391 X 3,337,672 8/1967 Steingrubner 425/391 X Primary Examiner-J. Spencer Overholser Assistant Examiner.lohn S. Brown Attorney, Agent, or FirmArthur B. Co1vin [57] ABSTRACT In a known process and apparatus for the production of a continuous row of linking components for a slide fastener, using a plastics thread, the plastics thread is shaped into a spiral over and between a series of studs by means of a thread guide. One of the ends of each whorl of the spiral is crushed by means of a punch to form a linking component, whilst holding the corresponding whorl between the studs. The invention provides the improvement in that, on the crushing-point side of each whorl, the corresponding portion of the thread is stretched out rectilinearly beyond the crushing point and facing the corresponding side face of the thread guide. The required point of the thread is then crushed against the thread guide, which is used as an anvil, the punch used being independent of the other working tools, and the folding back of the corresponding portion of the thread being performed only after the crushing has been carried out.

3 Claims, 8 Drawing Figures PATENTED JAN 2 2 i974 sum 2 or 2 DEVICE FOR THE MANUFACTURE OF A ROW OF LINKING COMPONENTS FOR A SLIDE FASTENER More specifically, it relates to a manufacturing process which consists of shaping such a thread into a spiral between a series of studs and crushing one of the ends of each whorl in order to constitute a linking component at the same time holding the corresponding whorl between two studs.

In order to be able to obtain this latter result, the notches between the studs must therefore be narrower in width than the linking components formed by crushing the thread. The thread is positioned between the studs by means of a thread'guide to which a to-and-fro movement is imparted in a direction parallel to its axis so as to place the thread first in one direction then in the other inside each notch. During this operation, the stud support is kept still, but a movement equal to the space between two of the notches is subsequently imparted to it to bring the next notch in front of the thread-guide.

Thus, on one of the sides of the spiral the thread is folded around studs which thus keep this spiral in position. On the opposite side, this spiral is held in the way already mentioned, i.e. by holding the flattened portion formed by each of the linking components made by crushing the thread.

In this connection, it should be noted that the punch used for this purpose consists of the thread-guide itself which has several disadvantages.

One of these is that this makes it necessary to arrange for this part to undergo a complicated movement. In fact, its to-and-fro movement must be combined with a movement in a direction parallel to one of the spokes of the toothed plate when the thread is crushed, and a complementary return movement.

Another disadvantage is that the strength of the pressure which can be exerted with the crushing punch is limited by the fact that the latter is integral with the thread-guide.

Yet another disadvantage is the fact that the crushing of the thread occurs on the edge of a portion of thread raised at right-angles. Now, this is detrimental to the obtention of linking components with exactly the required profile.

This is why this invention covers a new manufacturing process of the same kind, but which is so designed as to eliminate the disadvantages listed above.

This process is characterised in that on the crushingpoint side of each whorl, the thread is stretched out rectilinearly beyond this point, and facing the corresponding side face of the threadguide, and in that the required point along the thread is then crushed against this part, which is thus used as an anvil, while the punch used is independent of the other working tools, the thread being folded back subsequently.

This invention also covers a device specially designed for putting this manufacturing process into operation. A form of embodiment of this device is described below, together with an example of the operating of this process. This description is given with reference to the drawing attached as an indication only, wherein:

FIG. 1 is a partial sectional view of the manufacturing device in accordance with the invention, shown after the thread has been folded back,

FIG. 2 is a similar view showing this device at the moment when the thread-guide begins to stretch out a portion of thread rectilinearly, 1

FIGS. 3 to 5 are similar sectional views illustrating the later phases of manufacture,

FIGS. 6 to 8 are partial perspective views of the same device, showing it in the positions already illustrated in FIGS. 1, 4 and 5.

The device shown comprises a circular plate 1 equipped with studs 2 around its periphery. The width e of each of the latter corresponds to the required distance between two successive whorls of the spiral to be made out ofa plastic thread 3 to form a continuous row of linking components for a slide fastener.

Facing the plate I, there is a thread-guide 6 to which a to-and-fro movement is imparted in accordance with arrows F1 and F2 in a direction parallel to the axis of the toothed plate 1.

This part is transpierced from side to side by a hole 7 oriented radially in relation to the plate I. The plastic thread 3 is threaded through this hole so as to be placed by the thread-guide in the notches between the teeth .of the plate, as will be described in detail further on.

When the device is in operation, the thread is, of course, made to slide in the direction of the arrow F3 inside thehole 7 as the spiral is formed. Moreover, the thread-guide includes a brake designed to prevent any possibility of the thread going backwards. This brake consists of a push-rod 8 subjected to the action of a spring 9 and of which the end in contact with the thread is chamfered to prevent the latter going backwards, while allowing it to slide in the direction F3.

The plate I is mounted to rotate around its axis and is fitted with drive means capable of intermittently imparting to it an angular movement in the direction of the arrow F4, equal to the width E between two successive notches 10 in its periphery so that each of these is successively brought opposite the hole 7 in the threadguide 6. synchronisation of the latters drive means and those of the toothed plate 1 is such that the latters intermittent angular movement occurs after a whorl of the spiral has been formed.

Finally, a punch 11 is provided, designed to crush the thread 3 which can later form a linking component. This punch offers the peculiarity that it consists of a part which is independent of the other components of this device.

This punch 11 is positioned facing the face of the plate I towards which the thread 3 is first of all drawn. This punch has a simple to-and-fro movement imparted to it in a direction F5 parallel to the plate I and in the radial plane of the latter which passes through the outlet of the hole 7.

The end of this punch is positioned facing the corresponding flat face 6a of the thread-guide which can thus serve as an anvil when the thread 3 is crushed.

The drive means of this punch and those of the thread-guide are so synchronised that crushing takes place before folding of this portion of thread.

Moreover, by means of the particular mode of arrangement of this device, the manufacturing process covered by the invention is operated in the following manner:

After a whorl has been formed, the thread-guide 6 is in the maximum up position shown in FIG. I. At that moment, an angular movement E is imparted to the toothed plate 1 so as to bring its next empty notch opposite the hole 7 in the thread-guide. The effect of this movement is to exert a pull on the thread 3 which comes against the corresponding stud 2 of the plate, there forming a linking portion 12 between two succes' sive whorls of the spiral.

After this movement, the thread-guide 6 is moved in the direction of the arrow F], as shown in FIGS. 2 and 3. During this movement, the thread-guide exerts a pull on the plastic thread 3 which it deposits in the corresponding notch 10.

However, the mode of arrangement is such that the thread-guide continues its movement until it is in the position shown in FIG. 4 and is situated at a certain distance from the crushing punch 11.

In this position, the thread-guide has thus drawn a considerable length of thread beyond the latter, rectilinearly. This length extends facing the corresponding flat face 6a of the thread-guide, which is parallel to the axis of the toothed plate.

Immediately afterwards, the punch 11 is moved in the direction of the arrow F towards the thread-guide 6. In these circumstances, this punch crushes the thread 3 against the corresponding face 6a of this part, which then serves as an anvil. This crushing occurs at Point 13 and the section of the thread at this point is thus flattened and will later form one of the linking components of the row under manufacture.

Then, the thread-guide 6 again has a movement imparted to it, but in the opposite direction F2, the result of which is to exert a pull on the thread in this direction. This pull causes the corresponding portion of the thread to fold at its point of crushing 13.

This operation is facilitated by the presence of the brake 8. The whorl so formed is then held in the corresponding notch in the plate 1 against the pull exerted on the thread due to the fact that the flattened portion formed by the linking head 13 comes up against the corresponding face of the plate I.

The thread-guide then continues its movement until it reaches its maximum up position shown in FIG. I, after which the device is again ready to carry out a further working cycle as previously described.

Because of their particular design, the process and the device covered by the invention offer a number of advantages, in particular the following:

I. The shaping of the linking components is effected under optimum conditions, as the crushing of the thread is done on a rectilinear portion thereof. Moreover, a substantial length of thread is held rectilinearly against the corresponding face of the thread-guide beyond the crushing point. In these circumstances, the thread can spread out perfectly flat against the flat face 6a of the thread-guide which constitutes an anvil. This consequently makes it possible to obtain the shape required for each linking component very precisely. Now, the same does not apply to the former process mentioned previously, as in that process, the crushing of the thread is always done next to a folded, or at least partly bent, portion of thread.

The crushing punch 11 is completely independent of the other components of this device.

Because of this, much stronger pressure can be exerted with it than when it is carried by the thread-guide as is the case in the former process already mentioned. In fact, in the latter, the crushing punch is integral with the thread-guide, which limits the strength of the pressure which can be exerted by means of this punch.

Moreover, the independence of the crushing punch and the very nature of the corresponding anvil make it possible to provide for relievos or moulds on each of these two parts comprising any profile required to make specially shaped linking heads.

This is a substantial advantage as it is thus possible to obtain linking heads with various shapes which allow more efficient joining than in the case of fasteners made in accordance with the former process already mentioned.

As regards the way in which the linking heads are made, it should be noted that the crushing of the thread occurs on the side which will later correspond to the outside face of the fold made.

This peculiarity also helps to obtain linking heads with the precise shape required, which is not always the case when crushing occurs on the inside of the fold formed by the thread.

The movement of the thread-guide is very simple, since it is a to-and-fro movement in a direction parallel to the axis of the toothed plate.

Moreover, the crushing punch itself has an equally simple to-and-fro movement parallel to one of the spokes of this plate. The simplicity of these movements makes a very high rate of production possible. Now, this is not possible in the former process previously mentioned, which uses a thread-guide with a more complicated movement.

Moreover, the device covered by the invention has the advantage of comprising a very simple construction since it is made up of only three main components, i.e.: the toothed plate used to form the spiral, the threadguide also uses as an anvil, and finally the threadcrushing punch.

However, it goes without saying that the device in accordance with the invention is not confined to the single example of embodiment which has been described above merely as an indication.

I claim:

I. Apparatus for the production of a continuous run of linking components for a slide fastener using a plastic thread, comprising a forming member including a plurality of extending studs having spaces defined therebetween, forming member drive means for stepwisely moving said forming member selected increments to advance said studs in a selected path, thread guide means mounted for reciprocation in a linear path paralleling said spaces, said guide means including a thread feed aperture in proximate spaced relation to the ends of said studs and aligned with said spaces for placing the thread in position within the spaces between said studs responsive to said reciprocatory movement, an anvil portion on said guide means facing said studs, punch means disposed at one side of said path of said studs shiftable toward and away from said anvil for crushing a thread portion disposed on said anvil, thread guide drive means operatively connected to said thread guide means for shifting said guide means in said linear path between first and second limiting positions, respectively, with said feed aperture extending to the opposite side of said path from said punch means and with said aperture extending to the same side of said path as said punch means and beyond said punch means, said forming member drive means, thread guide drive means, and punch means operating in timed relation sequentially to shift said thread guide means from said first to said second limiting position to introduce said thread into a said space, energize said punch means to the thread crushing position after said aperture has passed said punch means to crush a portion of said thread in registry with said anvil, retract said guide means from said second to said first limiting position to fold said thread about said crushed portion, and intro duce a second thread increment into said space, and thereafter stepwisely move said stud containing forming member a selected increment to align said guide apear configuration when crushed by said punch. 

1. Apparatus for the production of a continuous run of linking components for a slide fastener using a plastic thread, comprising a forming member including a plurality of extending studs having spaces defined therebetween, forming member drive means for stepwisely moving said forming member selected increments to advance said studs in a selected path, thread guide means mounted for reciprocation in a linear path paralleling said spaces, said guide means including a thread feed aperture in proximate spaced relation to the ends of said studs and aligned with said spaces for placing the thread in position within the spaces between said studs responsive to said reciprocatory movement, an anvil portion on said guide means facing said studs, punch means disposed at one side of said path of said studs shiftable toward and away from said anvil for crushing a thread portion disposed on said anvil, thread guide drive means operatively connected to said thread guide means for shifting said guide means in said linear path between first and second limiting positions, respectively, with said feed aperture extending to the opposite side of said path from said punch means and with said aperture extending to the same side of said path as said punch means and beyond said punch means, said forming member drive means, thread guide drive means, and punch means operating in timed relation sequentially to shift said thread guide means from said first to said second limiting position to introduce said thread into a said space, energize said punch means to the thread crushing position after said aperture has passed said punch means to crush a portion of said thread in registry with said anvil, retract said guide means from said second to said first limiting position to fold said thread about said crushed portion, and introduce a second thread increment into said space, and thereafter stepwisely move said stud containing forming member a selected increment to align said guide aperture with the space between the next succeeding studs while said guide means is in said first limiting position.
 2. The apparatus Of claim 1 wherein said thread guide includes one way brake means engaging said thread for permitting payout of said thread through said aperture and preventing rectractile movements of said thread through said aperture.
 3. The apparatus of claim 2 wherein said brake means applies a drag to said thread during said payout movement whereby said thread is distended and in linear configuration when crushed by said punch. 